Silicon carbide (SiC) has been expected as a material for next generation semiconductor devices. As compared with silicon (Si), silicon carbide has superior physical properties that a band gap is three times of that of Si, a breakdown field strength is about ten times of that of Si, and a thermal conductivity is about three times of that of Si. These characteristics are utilized to achieve a SiC device capable of operating with a low loss at high temperature.
In order to improve characteristics of the SiC device, it is desirable to reduce a contact resistance of a metal electrode provided on an n-type impurity region. For example, the reduction in contact resistance of a backside electrode of the vertical SiC device is important from the viewpoint of reducing an on-resistance.